- Preheat the oven to 200C, and line a large baking tray with foil and baking parchment.
- In a large bowl, toss together the red and yellow peppers, onions, courgettes and garlic with the 3 tbsp of the olive oil. Season with salt and black pepper. Place in the oven for 20 minutes, until just beginning to brown.
- Remove the tray from the oven and stir the vegetables. Add the vine tomatoes and the salmon fillets, brushing with the remaining olive oil.
- Return to the oven for around 10 minutes until the salmon is just cooked through.
- Serve scattered with torn basil leaves.